The goals of this project are to establish a method of screening recombinant DNA using synthetic oligonucleotides as hybridization probes. The probes will be mixtures of oligonucleotides representing all possible codon combinations predicted from a particular peptide sequence of a protein. Stringent hybridization criteria will be used to allow the single correct sequence to hybridize to the correct cloned DNA. Various oligonucleotide probes will be synthesized chemically for the screening of the cloned DNA, including beta-2 microglobulin, H-2Kb antigen, HLA-D antigen, PGK, glucagon and others.